As of iOS 6, Apple thought Unwind Segues would be added to their layout/views. What this means is, when you're on the 7th view of a stack, you can pop back to any other one. For those of you pure OO fans (like myself), I cringed a little. I cringed even more when I learned these also work with pop-ups.
Why would a modal on top of a stack know about the Nth view before?
I'm a big fan of OO because when you stick to its principles, you don't get spaghetti. And once you have a complex set of modals that are shared among multiple navigation controllers, these Segues begin to cluster into a bunch of lines on your storyboard that effectively don't enhance the navigation (as compared to an Obj-Oriented solution), but take up space on your Storyboard.
If you change a parent view, you immediately break the unwind segue and have to edit all the code that pointed to it, which is one of the exact same reasons we avoid doing this in code.
This has made me cringe for awhile, and I don't see any questions that bring this up in relation to views.